Editor’s Note: Suppose you had a faulty culvert that was all set to be retrofitted to improve fish passage, and suppose a particularly tempestuous storm called Irene came to call! Courtesy of our friends at Trout Unlimited, here’s the story of what happened to the Woodlawn Cemetery culvert on Nason Brook in Rochester, VT under just those circumstances:
The pre-Irene culvert in Woodlawn Cemetery was an 11-foot multi-plate pipe arch with cement wingwalls, header, and an 8-inch perched outlet apron. The site is located a quarter mile from the mainstem White River in Rochester, Vermont. In 2010, project partners identified this structure as a complete barrier to trout of all sizes and designed, permitted and scheduled a fish passage retrofit project. In August 2011, Tropical Storm Irene destroyed the road and culvert, postponing the restoration.
Nason Brook’s bankfull width is 22 feet, and the 11-foot wide structure acted like a dam during Irene flooding. Floodwaters were forced to bypass around the culvert on river left, washing out 60 graves from the cemetery, before removing and pushing the culvert structure downstream. After the flood, the town put the culvert back in place temporarily, as a way to walk to the cemetery annex.
Following the flood, the White River Partnership (WRP) secured funding from the Green Mountain National Forest, Orvis / Trout Unlimited, and US Fish & Wildlife Service (USFWS) National Fish Passage Program to help the Town of Rochester increase the size of the replacement culvert the Federal Emergency Management Administration (FEMA) would fund.
FEMA can only fund culvert replacements sized to meet the town’s adopted Codes and Standards, which required new culverts to pass stormwater flows equal to a Q25 or 25-year-flood event. With additional funds from the State of Vermont, project partners hired a local engineer to design a replacement structure that was both flood-resilient, fish-friendly and was able to pass the Q100 storm flows.
Because the stream crossing at Woodlawn Cemetery only provides access to the cemetery annex, project partners explored low-cost replacement options and decided to purchase a used 34-foot steel I-beam bridge. The bridge was installed during late summer 2013, opening up 2.1-miles of upstream habitat.
Monitoring confirms that fish passage has been restored at the stream crossing: USFWS biologists tagged brook trout downstream of the culvert before project implementation and then found tagged fish upstream of the bridge post restoration.
Project partners include the Green Mountain National Forest, Eastern Brook Trout Joint Venture, Orvis/Trout Unlimited 1,000 Miles Campaign, FEMA, State of Vermont, Town of Rochester, T.R. Fellows Engineering, and USFWS National Fish Passage Program.